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41.
Allogeneic marrow transplantation in patients with chronic myeloid leukemia in the chronic phase: a randomized trial of two irradiation regimens 总被引:1,自引:5,他引:1
R A Clift C D Buckner F R Appelbaum E Bryant S I Bearman F B Petersen L D Fisher C Anasetti P Beatty W I Bensinger 《Blood》1991,77(8):1660-1665
A randomized trial was performed to compare two regimens of total body irradiation in patients with chronic myeloid leukemia treated by allogeneic marrow transplantation while in the chronic phase. All patients received cyclophosphamide 120 mg/kg followed by total body irradiation and marrow from HLA-identical siblings. Cyclosporine and methotrexate were used for prophylaxis against acute graft-versus-host disease. Fifty-seven patients were randomized to receive 2.0 Gy fractions of irradiation daily for 6 days and 59 were randomized to receive 2.25 Gy fractions daily for 7 days. The probabilities of relapse at 4 years were 0.25 for the 12.0 Gy group and 0.00 for the 15.75 Gy group (P = .008). The actuarial probabilities of survival and relapse-free survival at 4 years were 0.60 and 0.58 among the patients who received 12.0 Gy compared with 0.66 and 0.66 for those who received 15.75 Gy. The 4-year probabilities of transplant-related mortality were 0.24 and 0.34 respectively (P = .13) while the probability of moderate to severe acute graft-versus-host disease was 0.33 for the 12.0 Gy group and 0.44 for the 15.75 Gy group (P = .15). The lower relapse probability in the patients receiving the higher dose of total body irradiation did not result in improved survival because mortality from causes other than relapse was increased. 相似文献
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Brandon P. Verdoorn MD Tamara K. Evans BS Gregory J. Hanson MD Yi Zhu PhD Larissa G. P. Langhi Prata PhD Robert J. Pignolo MD PhD Elizabeth J. Atkinson MS Erin O. Wissler-Gerdes MA George A. Kuchel MD Joan B. Mannick MD Stephen B. Kritchevsky PhD Sundeep Khosla MD Stacey A. Rizza MD Jeremy D. Walston MD Nicolas Musi MD Lewis A. Lipsitz MD Douglas P. Kiel MD Raymond Yung MB ChB Nathan K. LeBrasseur PhD Ravinder J. Singh PhD Teresa McCarthy MD MS Michael A. Puskarich MD Laura J. Niedernhofer MD PhD Paul D. Robbins PhD Matthew Sorenson JD MA Tamara Tchkonia PhD James L. Kirkland MD PhD 《Journal of the American Geriatrics Society》2021,69(11):3023-3033
The burden of senescent cells (SnCs), which do not divide but are metabolically active and resistant to death by apoptosis, is increased in older adults and those with chronic diseases. These individuals are also at the greatest risk for morbidity and mortality from SARS-CoV-2 infection. SARS-CoV-2 complications include cytokine storm and multiorgan failure mediated by the same factors as often produced by SnCs through their senescence-associated secretory phenotype (SASP). The SASP can be amplified by infection-related pathogen-associated molecular profile factors. Senolytic agents, such as Fisetin, selectively eliminate SnCs and delay, prevent, or alleviate multiple disorders in aged experimental animals and animal models of human chronic diseases, including obesity, diabetes, and respiratory diseases. Senolytics are now in clinical trials for multiple conditions linked to SnCs, including frailty; obesity/diabetes; osteoporosis; and cardiovascular, kidney, and lung diseases, which are also risk factors for SARS-CoV-2 morbidity and mortality. A clinical trial is underway to test if senolytics decrease SARS-CoV-2 progression and morbidity in hospitalized older adults. We describe here a National Institutes of Health-funded, multicenter, placebo-controlled clinical trial of Fisetin for older adult skilled nursing facility (SNF) residents who have been, or become, SARS-CoV-2 rtPCR-positive, including the rationale for targeting fundamental aging mechanisms in such patients. We consider logistic challenges of conducting trials in long-term care settings in the SARS-CoV-2 era, including restricted access, consent procedures, methods for obtaining biospecimens and clinical data, staffing, investigational product administration issues, and potential solutions for these challenges. We propose developing a national network of SNFs engaged in interventional clinical trials. 相似文献
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Kahli Zietlow MD Leslie Dubin MSW Alethia Battles JD MSW Caroline Vitale MD 《Journal of the American Geriatrics Society》2022,70(11):3070-3079
Guardianship may pose an ethical dilemma for physicians, who must balance protecting vulnerable patients from potential safety concerns with respecting their autonomy. Older adults with dementia are particularly susceptible to loss of independence and the ability to participate in medical decision making. To have the capacity for medical decision making, individuals must understand relevant information, appreciate their circumstances, demonstrate reasoning, and express a consistent choice free from coercion. Although capacity assessments are usually task-specific, geriatricians and other specialists may be asked to comment on capacity more globally. These determinations may be used to support a Petition for the Appointment of a Guardian of a Legally Incapacitated Adult, the legal process of pursuing guardianship in probate court. Assigned guardians may be known to the incapacitated individual (e.g., a family member or friend) or may be professional guardians with no prior relationship to the ward. Guardians are encouraged to use substituted decision-making, taking into account the ward's previously expressed values and preferences. Although a number of viable alternatives to guardianship exist, numerous systemic barriers may prevent these from being fully explored. The ongoing need for guardianship should be periodically revisited and reassessed. Data about guardians and wards is shockingly sparse, as there are no centralized databases. Laws and regulations for guardianships vary significantly between states. Physicians can serve as important allies and advocates for patients with cognitive impairment at risk of incapacity, can help preserve their autonomy for as long as possible, and ensure appropriate protections are in place if the patient does lose their decision-making ability. 相似文献
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W. I. Bensinger K. Longin F. Appelbaum S. Rowley C. Weaver K. Lilleby T. Gooley M. Lynch T. Higano J. Klarnet T. Chauncey R. Storb C. D. Buckner 《British journal of haematology》1994,87(4):825-831
Factors affecting mobilization and engraftment were analysed in 54 patients undergoing transplant using autologous PBSCs mobilized with high-dose recombinant granulocyte stimulating factor (rhG-CSF). Patients received 5-7 d of rhG-CSF. 16 μg/kg/d, administered subcutaneously. PBSCs were harvested by leukapheresis using automated continuous-flow blood cell separators beginning on day 4 of rhG-CSF, processing 10 litres of whole blood, for 2-6 consecutive days. Transplants were performed for the following diseases: breast cancer (n = 22), non-Hodgkin's lymphoma (n = 18), multiple myeloma (n = 7) and other (n = 7). Engraftment was rapid with patients reaching a neutrophil count of 1 × 109 /1a median of 12 d (range 9-22) after transplant. Platelets > 20 × 109 /1 independent of transfusion support were achieved a median of day 10 (range 7-60) after infusion. Multiple factors potentially influencing engraftment were examined using a Cox regression model. The number of CD34+ cells per kg was highly correlated with the time to achievement of granulocyte and platelet recovery (P < 0.012, 0.0001). The use of a post-infusion growth factor and a radiation preparative regimen was important for neutrophil recovery, and a diagnosis of breast cancer was important for platelet recovery. In an analysis by linear regression of the logarithm of CD34+ cells collected, lower age, marrow without disease, no prior radiation, and lower number of prior chemotherapy regimens, were important factors influencing larger numbers of CD34+ cells in collections. 相似文献
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